Other class

Date : 2019-05-09

Screw, an inconspicuous object in daily life, plays an important role of machine in some occasions. There are three main types of screws: ordinary screws, self-tapping screws and expansion screws.

1.Ordinary screws

The screw is a tool that uses the physical and mathematical principles of the circular rotation and friction of the bevel of the object to gradually tighten the objects and parts. Screw is a common term for fasteners, spoken daily. Screws are an indispensable industrial necessity in daily life: very small screws used in cameras, glasses, clocks, electronics, etc.

2.Self-tapping screws

Generally refers to pointed, coarse-toothed, harder wood screws, but also aluminum alloy and plastic. A special type of self-tapping screw for threading a metal hole is called a tap.

3.Expansion screws

Expansion screws are generally referred to as metal expansion screws. The expansion screws are fixed by using a wedge-shaped slope to promote expansion to produce frictional grip and achieve a fixing effect. The screw is threaded at one end and tapered at one end.

There are three main types of screws: ordinary screws, self-tapping screws and expansion screws.

Anti-corrosion technology for screws:

Stainless steel screws are made of metal, and there are four main methods for metal corrosion protection, namely the nature of the material, the environment in which it is used, the interface between the data and the environment, and the design to improve the metal structure. Unless there is a special need, it is not practical in terms of economic concepts, or it is difficult to completely isolate the appearance of the screw from the environmental elements that will cause corrosion, which may not be feasible in practice.

Improving the design of the metal structure can improve the impact of special circumstances under certain conditions, but the design of most stainless steel screws cannot be fully modified, and its maintenance effect is not eternal. Therefore, this method cannot basically deal with the problem. Corrosion protection, that is, the appearance of anti-corrosion treatment is the most widely used method.

Stainless steel screw surface anti-corrosion treatment refers to the application of various methods to apply a maintenance layer on the metal surface. Its role is to isolate the metal from the corrosive environment to prevent the corrosion process from occurring or to reduce the contact between the corrosive medium and the metal surface. The purpose of avoiding or mitigating corrosion.